function isObj(val) {
  return Object.prototype.toString.call(val).slice(8, -1) === "Object";
}

const obj = {
  a: 10,
  b: 10,
  c: 10,
  d: {
    key2: 10,
  },
};
const obj1 = {
  a: 1,
  b: {
    key1: 1,
  },
  c: [1],
  d: {
    key1: 1,
  },
};
const obj2 = {
  a: 1,
  b: {
    key1: 1,
  },
  c: [1],
  d: {
    key1: 1,
  },
};
const obj3 = {
  a: 1,
  b: {
    key1: 1,
  },
  c: [1],
  d: {
    key1: 1,
  },
};
const obj4 = {
  a: 1,
  b: {
    key1: 1,
  },
  c: [1],
  d: {
    key1: 1,
  },
};
const obj5 = {
  a: 1,
  b: {
    key1: 1,
  },
  c: [1],
};

var name = "xu";
var person = {
  name: "liu",
};
function sayHello(age) {
  return `Hello, I am ${this.name}, I am ${age} years old.`;
}
function Person1(name) {
  this.name = name;
}
function Person2(name) {
  this.name = name;
  return "Hello, name";
}
function Person3(name) {
  this.name = name;
  return {
    name: this.name,
    age: 20,
  };
}
